South Korean foreign minister Yu Myung-Hwan on Sunday expressed scepticism about North Korea's recent overtures to resume stalled six-party talks on its nuclear disarmament.
Pyongyang was just trying to deflect away pressure after being blamed by Seoul and its allies for sinking a South Korean warship in March, Yu told state television.
"It is very regrettable that (North Korea) is trying to abuse the six-party talks to make an excuse to shun the global attention to the Cheonan incident," Yu told KTV.
The North said on July 10 that it was willing in principle to return to nuclear disarmament talks after the United Nations failed directly to blame it for the deadly attack on the Cheonan, which left 46 sailors dead.
The talks -- grouping the two Koreas, the United States, China, Japan and Russia -- have been stalled since North Korea quit them in April 2009.
The North has previously expressed willingness in principle to return. But first it wants the US to agree to hold talks on a peace treaty formally ending the 1950-53 war and an end to sanctions.
"It is not time to discuss resuming six-party talks with some North Korean strings attached," Yu said.
The South and the United States, citing findings of a multinational investigation, accuse the North of torpedoing the warship, but the North angrily denies involvement. The UN Security Council issued a statement on July 9 which condemned the attack without specifying the culprit.
Meanwhile, South Korea plans to punish dozens of its military brass for negligence of duty over the sinking, Yonhap news agency said on Sunday.
Yonhap, citing unnamed military sources, said military prosecutors were in their final stage of having those officers court-martialed.
However, the defence ministry declined to confirm the report.
Seoul's state audit agency last month found 25 military officers, including 13 generals, guilty of negligence of duty, with Lee Sang-Eui, then chairman of the Joint Chiefs of Staff, resigning.